Goniometer



March 21, 1961 Filed Oct. 6, 1958 G. SCHMUCKER ETAL 2,976,531

GONIOMETER 3 Sheets-Sheet 1 INVENTORSZ GEORG SCHMUCKER, ALBERT TROOST, GUNTER ZIEHM,

KURT ZEHENDER PATENT AGENT March 21, 1961 G. SCHMUCKER EI'AL 2,976,531

GONIOMETER Filed Oct. 6, 1958 3 Sheets-Sheet 2 Fig.3

GEORG SCHMUCKER' A|,. BERT TROOST, GUNTER ZIEHM, KURT ZEHENDER BY Zzfl PATENT AGENT March 21, 1961 G. SCHMUCKER EI'AL 2,976,531

GONIOMETER Filed Oct. 6, 1958 3 Sheets-Sheet 3 Fig. 4

INVENTORS GEORG SCHNIUCKER, AEBERT TROOST, GUNTER ZIEHM,

KURT ZEHENDER PATENT AGENT GONIOMETER Georg Schmucker, Albert Troost, Gunter Ziehm, and

Kurt Zehender, all of Ulm (Danube), Germany, assignors to Telefunken G.m.b.H., Berlin, Germany Filed Oct. 6, 1958, Ser. No. 765,421 Claims priority, application Germany Oct. 18, 1957 8 Claims. (Cl. 343-424) The present invention relates to a ring goniometer.

It is well known that the phase shift between the voltages induced in individual antennas depends upon the direction of incidence of the wave to be measured. The maximum phase shift between the voltages induced in two diametrically oppositely arranged Adcock antennas or in the vertical members of a loop antenna is determined by the spacing between said individual antennas or said vertical loop members and is not large, since the spacings in directional antenna systems are usually small, as compared with the operating wave length.

Figures 1 and 2 relate to the prior art, Figure 2 illustrating a known form of antenna described in terms of the vector diagram of Figure 1.

Figure 1 shows the voltage vectors Uantl and U of two separate antennas of an Adcock system arranged diametrically opposite each other. These two voltage vectors are shifted by an angle The two voltage vectors shown in Figure 1 can be resolved, as known, into in-phase components U and U and into components U 1 and U 2 in phaseopposition. In a goniometer, the components in phaseopposition of the received voltage give rise to a direc tional flux, while the in-phase components thereof create an annular flux in the goniometer core.

A closer approach to these well known conditions will now be made with reference to Figure 2. For the sake of clarity, the search winding of the goniometer is not illustrated in this figure and, for the sake of simplicity, there are shown only two diametrically opposed dipoles 1 and 2 of an antenna system with their associated windings 4 and 5 which surround an iron core 3. As mentioned in the foregoing, the voltage components in phaseopposition give rise to a directional flux which is indicated by a dash-dot line in Figure 2 and denoted by H. This directional flux does not have its return path within the iron core, but leaves it and flows across the free space in the center of the iron core, then re-enters the iron core at a place which is diametrically opposite the exit point. The above-mentioned annular flux, however, which is produced by the in-phase components of the received voltage, remains substantially within the iron core. The annular flux is represented by a broken line and denoted by H. The directions of the directional flux H and the annular flux H indicated by the arrows will be considered as instantaneous values.

The directional flux H is used for direction finding purposes. If the annular flux would flow within the iron core only, it would not create a problem. However, with less than perfectly symmetrical iron core, components of the annular fiux H leave the core and become superimposed upon the directional flux H, thus confusing the final results.

It is an object of the present invention to eliminate said spurious annular flux.

It is another object of the invention to provide a ring goniometer having the ends of two diametrically opposed windings connected to each other so that the in-phase Fatented Mar. 21, 1961 components of the received voltage are short circuited, said connection means, however, having no influence on the current components which induce the directional flux.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Figure 3 is a schematic diagram of a system embodying the improvements of the present invention. Figure 4 shows schematically an embodiment of the invention in which the auxiliary voltage is obtained by auxiliary windings, each of these being inserted in one of the conductors, which connect the ends of two diametrically opposed windings.

The embodiment of the present invention comprises an Adcock antenna system including four dipoles 6, 7, 8 and 9. Windings 10, 11, 12 and 13 wound on the iron core 18 are connected to the dipoles 6, 7, 8 and 9, re-

spectively. For the sake of symmetry and in order to insure that the windings will be balanced, the centers of these windings are grounded. Between the terminal 19 of the winding 10 and the terminal 20 of the winding 12, there is connected a conductor 14. In a similar way, the conductors 15, 16 and 17 are interconnected between the respective terminals of two diametrically opposed windings.

The instantaneous phases of the voltage components are indicated at the respective ends of the dipoles. The signs outside the parentheses represent the phase of the components in phase-opposition which induce the directional flux, while the signs inside the parentheses indicate the phase of the in-phase components which induce the annular flux.

The operation of the goniometer according to the invention will be explained more fully with reference to the diametrically opposed dipoles 6 and 8. In the upper part of the dipole 6, the in-phase component (in parentheses) is positive. Positive potential prevails also at the terminal 19. At the same instant, a negative potential prevails at the terminal 21 of the winding 10 and at the terminal 20 of the winding 12. The current flowing because of the potential difference does not flow from the terminal 19 via the inductive reactance of the winding 10 to the terminal 21, but via the non-inductive conductor 14 to the terminal 20 and the lower half of the dipole 8.

At the terminal 19 of the winding 10, the voltage component in phase-opposition is negative. Similarly, a negative potential prevails at the terminal 26 of the winding 12. However, a positive potential appears at the terminal 21 of the winding 10. The voltage component in phase opposition can only give rise to a current through the winding 19, since the two conductors 14 and 15 have both ends thereof at the same potential, so that no current is made to flow by the voltage components in phaseopposition.

The same consideration can be applied to the other windings and conductors. The same result will always be obtained, namely, the in-phase components of the received voltages are short-circuited by the conductors, so that the current generating the annular flux through the field winding is eliminated without any influence on the components inducing the directional flux.

In the systems known per se, annular flux present often was used to produce an auxiliary voltage which could be utilized in place of a voltage such as derived from an auxiliary antenna. For this purpose, one or more additional windings, were arranged on the iron core and the voltage induced was used as auxiliary voltage for sense determination.

With the arrangement according to the present invention, such an auxiliary voltage can be produced by utilizing the compensating currents flowing through the conductors 14, 15, 16 and 17. For this purpose, an auxiliary winding is inserted in each conductor. Such an arrangement is represented in Fig. 4. Similar partsofthe Figs. 3 and 4 are marked with the same symbols. The auxiliary windings inserted in each conductor are marked 22, 23, 24 and 25'. The two auxiliary windings 22 and 23 in the conductors 14 and 15 are coupled in the additive direction to a separate secondary winding 26. In the same manner the auxiliary windings 24 and 25 are coupled with the secondary winding 27. Both secondary windings 26 and 27 are connected in series and the auxiliary voltage is derived from the terminals 28 and 29 of this series connection. Transformers for producing said auxiliary voltage may have ferrite cores.

The arrangement described above is not to be limited to ring goniometers having four dipoles and is given only by way of example.

In addition to goniometers, the invention may be applied to coordinate transformers. Such coordinate transformers are constructed similar to ring goniometers. For

example six windings are arranged on the iron core. Instead of one rotary search winding (not shown in Figs. 3 and 4) in case of a coordinate transformer two fixed windings are provided, arranged at right angles. Because there is no great difference between the illustration of a ring goniometer and a coordinate transformer according to the invention it is not necessary to illustrate the coordinate transformer. I

We claim:

1. In a goniometer for connection with antenna means, said goniometer including a core ring and including at least two pairs of field windings wound in diametrically opposite locations on the core ring, and having terminals at the ends of the windings connected with said antenna means, means for short-circuiting the in-phase components of volt-ages across the paired windings while leaving the phase-opposition components undisturbed, comprising conductors joining between opposite windings the terminals at which the components of the voltages, which would generate a purely annular flux in the core ring, are of opposite polarity.

2. In a goniometer according to claim 1, each of the windings having a center tap and all of the center taps being grounded.

3. In a goniometer according to claim 1, at least one of said conductors having output means associated therewith, whereby a signal may be obtained proportional to the current flowing in the conductor. 7

4. In a goniometer according to claim 3, each of said output means comprising a transformer having a primary winding connected in series with the associated conductor and having a secondary winding delivering said signal.

5. In a coordinate transformer for connection with antenna means and having a core ring and having at least four windings arranged in mutually perpendicular pairs, and each winding having end terminals connected with said antenna means, means for short-circuiting from the paired windings the in-phase components of voltages thereacross while leaving the phase-opposition components undisturbed, comprising conductorsjoining in opposite windings the terminals at which the components of the voltages which would generate a purely annular flux in the core ring are of opposite polarity.

6. In a transformer according to claim 5, each of the windings having a center tap and all of the center taps being grounded. a

7; In a transformer according to claim 5, at leastone of said conductors having output means associated'therewith, whereby a signal may be obtained proportional to the current flowing in the conductor.

8. In a transformer according to claim 7, each of said output means comprising transformer means having a primary winding connected in series with the associated conductor and having a secondary winding delivering said signal.

No references cited. 

